Process and apparatus for producing low boiling point hydrocarbon oils



June 23, 1931. c. P. DUBBS 1,811,399

PROCESS AND APPARATUS FOR PRODUCING LOW BOILING POINT HYDROCARBON OILSOriginal Filed May 1920 COOLER FUR/Y/ICE VAPOR luv:

331 1424440 abkozwuz Patented June 23, 1931 UNITED {STATES PATENT OFFICECARBON P. DUBBS, OF WILMETTE, ILLINOIS, ASSIGNOR TO UNIVERSAL OILPRODUCTS COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF SOUTH DAKOTA.

PROCESS AND APPARATUS FOR PRODUCING LOW BOILING POINT HYDROC ARBON OILSApplication filed November 1, 1928, Serial No. 316,565, in turn acontinuation of application Serial No. 381,922, filed Kay 17, 1920.Divided and this application filed March 21, 1930. Serial No. 437,764.

This application is a division of my copIending application Serial No.316,565, filed ovember 1, 1928, in turn a continuation of my applicationSerial No. 381,922, filed May 17, 1920.

My invention relates to improvements in a process and apparatus forproducing lower boiling point hydrocarbon oils and refers moreparticularly to a process in which the character of the distillateiscontrolled by regulation of the dephlegmating temperature.

Among the salient objects of the invention, are to provide a process inwhich the temperature of the dephlegmating or condensing agent iscontrolled so that either a large or small percenta eof the vaporsreleased from the oil body are condensed in passing therethrough; toprovide a process in which the temperature of the successive stages ofdephlegmation may be varied so that the oil vapors may be treated toproduce the greatest possible yield, a more uniform distillate, or sotreated that any particular cut or fraction may be extracted from theoil without necessitating the redistilling of the distillate procured;to provide an apparatus for the carryin out of the process and ingeneral to provi e an apparatus of the character referred to.

The single figure is a diagrammatic side elevation of the apparatus withparts in section.

disintegration of the molecules in the reacting chamber, the distillatewhiclris produced by the condensation of these 011 vapors 1s roduced inan inversed relation to the way in which they are cracked, that is, withthe heating of the oil, the low boiling point hydrocarbons will first bereleased from the oil body, subsequently as the temperature isincreased. the higher boiling point hydrocarbons will come off. So, withthe cooling of the vapors, the high boiling point oils will first becondensed and subsequently'as the temperature is decreased, low boilingpoint vapors will be liquefied. From this, it Will be seen that themethod and means of cooling or condensing the oil vapors is of as Incracking hydrocarbon oils, after the.

much importance as the heating thereof. By the controlling of thetemperature at which the cendensation takes place, the character of thedistillate may be controlled. The controlling of this condensatingtemperature is the most important function of the following process.

Referring in detail to the drawing, the raw oil is mtroduced from anyconvenient source to the dephlegmator 1 through the inlet pipe 2, whichis regulated by valve 3.

The raw oil together with condensate condensed in the dephlegmator lcollects in vertically arranged pools, 4, 5 and 6, the levels of whicharecontrolled by standpipe 6a which convey the surplus oil from eachpool to the pool below. The oil, after dephlegmating the oil vaporswhich bubble up through the pools by means of risers 7, collects in thebottom of the dephlegmator and is drawn off through the line 8, which iscontrolledby valve 9. This .oil contain- 1ng what condensate it maycollect in dehlegmating the vapors is charged to the eating coils 10through the pump 11, charging pipe 12, controlled by valve 13. Theheating coils are mounted above the furnace 14, which is heated by anysuitable means (not shown The heated oil vapors, after being raise to acracking temperature, are directed to the reacting or vapor chamber 15through the pipe 16 which is regulated by valve at 17 One or more ofthese vapor chambers may be interposed in the system according-to thequantity of oil to be treated. The vapor chamber shown at 15 is equippedwith yrometer 18, pressure auge 19 and remova le cleaning plates 20. gresiduum draw-off 21 controlled by valve 22, furnishes a means forremoving the heavy residual oil, together with the precipitated carboncollecting in the vapor chamber. The vapors released from the oil bodyare directed through the risers 23 to the line 24 by means of which theare introduced to the bottom of the dephlegmator. As explained, thevapors rise through the successive pools through the risers 7 bubblingup through the raw oil in each pool and what vapors are not condensed inthese successive pools are drawn oil through the gooseneck 25, which iscontrolled byvalve 26. These vapors, after being subjected to thecooling effect of the water condenser 27, collect as a distillate in thereceiving tank 28. This receiving tank is equipped with pressure gauge29, liquid level gauge 30, liquid draw-off 31, controlled by a valve 32,and a gas relief pipe 33, controlled by valve 34. The water condenser 27is fitted with a water inlet pipe and an outlet pipe 36.

If it is desired to decrease the temperature of the liquid oil containedin either of the pools 4, 5 or 6, the same may be drawn oil through thelines 37 and forced by the pumps 38 through the cooling water condensers39, from which they-are directed back to to their respective pools bymeans of the return lines 40. It is essential that the valves 41 and 42are open during this local 37 and directed down through the lines 37a,

and circulated by means of the pumps 45 through the heating coils 46mounted above suitable heating means 47, after which the heated oilproceeds back to their respective pools through the return lines 48 andthrough a short connecting section of .the return lines 40. It isessential during this circulation that the valves 43 and 44 are in .anopen position and the valves 41 and 42 are closed.

In this manner, when it is desired to obtain a distillate containingonly the more volatile hydrocarbons such as the naptha and benzinecontent, the temperatures of the pools must be lowered so that the highboiling point h drocarbons will be condensed therein, the lighter ormore volatile oil vapors bubbling through the successive pools andfinally condensed as low boiling point distillate in the receiver 28.Thus, by controlling the temperature of the dephlegmating agent, thequantity and character of the distillate finally connected in thereceiver may be positively controlled. It may be an advantage to havethe dephlegmating agent in one pool relatively cool and in another poolhot. In this case, the liquid from the first pool may be circulatedthrough the cooling condenser while the liquid in the second pool may bedirected through the heater by a manipulation of the valves in therespective lines.

Having thus described my invention, what I desire to secure by LettersPatent is:

1. In the art of fractional distillation of petroleum, the process whichcomprises passing vapors upwardly through a plurality of fractionatingzones at difi'erent levels, passing reflux liquid downwardly in acontinuous stream through said zones countercurrent to and in contactwith said vapors, withdrawing liquid from one of said zones and coolingit, and returning liquid so cooled to a zone at least as high as thezone from which it was Withdrawn.

2. In the art of fractional distillation of petroleum, the-process whichcomprises passing vapors through a plurality of fractionating zones,passing reflux liquidin a continuous stream through said zonescountercurrent to and in contact with said vapors, withdrawing liquidfrom one of said zones and cooling it, and returning liquid so cooled tothe zone from which it was withdrawn.

3. In the art 'of fractional distillation of petroleum, the processwhich comprises passing vapors of the oil through a plurality offractionating zones, passing reflux oil in a continuous stream throughsaid zones countercurrent to and in contact with the vapors,circulatingliquid oil from and back to one of saidzones, and cooling theliquid oil while in circulation external to said zone.

4. In the art of fractional distillation of petroleum, the process whichcomprises passing vapors of the oil upwardly. through a plurality offractionating zones at different levels, passing reflux oil downwardlyin a continuous stream through said zones countercurrent to and incontact with the vapors, circulating liquid oil from one of said zonesback to a zone at least as high as the zone from which it is withdrawn,and cooling the liquid oil while in circulationexternal to said zones.

5. A fractionating system for petroleum comprising a fractionatingcolumn, means therein for defining a plurality of fraction atingchambers at different levels, means within said column for conductingreflux liquid in a continuous stream downwardly therethrough, means forpassing vapors of the liquid to be fractionated upwardly throughthecolumn countercurrent to and in contact with the reflux liquid,cooling means external to said column, and connections for withdrawingliquid from one of said chambers to said cooling means and for returningit to a chamber at least as high

